Manipulating the Temperature of Sulfurization to Synthesize α-NiS Nanosphere Film for Long-Term Preservation of Non-enzymatic Glucose Sensors

Abstract

In this study, alpha nickel sulfide (α-NiS) nanosphere films have been successfully synthesized by electroplating the nickel nanosheet film on the indium tin oxide (ITO) glass substrate and sulfuring nickel-coated ITO glass substrate. First, we electrodeposited the nickel nanosheet films on the ITO glass substrates which were cut into a 0.5 × 1 cm2 size. Second, the nanosheet nickel films were annealed in vacuum-sealed glass ampoules with sulfur sheets at different annealing temperatures (300, 400, and 500 °C) for 4 h in vacuum-sealed glass ampoules. The α-NiS films were investigated by using X-ray diffraction (XRD), variable vacuum scanning electron microscopy (VVSEM), field emission scanning electron microscopy/energy dispersive spectrometer (FE-SEM/EDS), cyclic voltammogram (CV), electrochemical impedance spectroscopy (EIS), ultraviolet/visible/near-infrared (UV/Visible/NIR) spectra, and photoluminescence (PL) spectra. Many nanospheres were observed on the surface of the α-NiS films at the annealing temperature 400 °C for 4 h. We also used the high-resolution transmission electron microscopy (HR-TEM) for the analysis of the α-NiS nanospheres. We demonstrated that our α-NiS nanosphere film had a linear current response to different glucose concentrations. Additionally, our α-NiS nanosphere films were preserved at room temperature for five and a half years and were still useful for detecting glucose at low concentration.

Nanoscale Ni(OH)x Films on Carbon Cloth Prepared by Atomic Layer Deposition and Electrochemical Activation for Glucose Sensing

“…It is worth noting that no Raman bands were observed at low bias potential (0−0.4 V) probably because the relevant vibrations for Ni(OH) 2 (e.g., at 445−465 cm −1 ) have much lower Raman cross sections. 42,43,47 Notably, a few prior works have reported the direct use of solution-phase synthesized NiS x nanomaterials, by either a solvothermal 48−54 or an electrodeposition method, 23,55 for the glucose sensing (Table S2). However, none of those works had carefully characterized the NiS x nanomaterials after the sensing experiment; it is highly possible that at least the surface of those NiS x nanomaterials was converted to Ni(OH) x during the sensing, and the latter was the de facto electrocatalyst for the glucose sensing.…”

“…Two bands at 474 and 557 cm –1 were observed at a high bias potential ranging from 0.45 to 0.70 V. These bands can be attributed to Ni–O vibrations in NiOOH, which are known to have high Raman cross section due to the resonance effect. ,, These observations clearly indicate that NiOOH was present at the high bias potential for the glucose sensing, thereby corroborating the aforementioned glucose sensing mechanism. It is worth noting that no Raman bands were observed at low bias potential (0–0.4 V) probably because the relevant vibrations for Ni­(OH) 2 (e.g., at 445–465 cm –1 ) have much lower Raman cross sections. ,, Notably, a few prior works have reported the direct use of solution-phase synthesized NiS x nanomaterials, by either a solvothermal − or an electrodeposition method, , for the glucose sensing (Table S2). However, none of those works had carefully characterized the NiS x nanomaterials after the sensing experiment; it is highly possible that at least the surface of those NiS x nanomaterials was converted to Ni­(OH) x during the sensing, and the latter was the de facto electrocatalyst for the glucose sensing.…”

Controlling of Ni-Based Composites in Salt Melt Synthesis with High Sodium-Ion Storage Performance

“…Obviously, their Nyquist plots contained a semicircle in the medium−high-frequency region and a line in the low-frequency region, which was similar to the previous reports. 54,55 As is well-known, the semicircle in Nyquist plots could be divided into two parts: a semicircle at high frequencies, corresponding to resistance and SEI resistance (R s ), and a semicircle in the medium-frequency region, derived from the charge transfer resistance (R ct ) on the between the electrode materials and electrolyte. 56 Similarly, in Figure 7d−f, the semicircle area of the as-prepared samples was first reduced and gradually enhanced during the cycling test, probably corresponding to the broken of structure that is illustrated in Figure 5.…”

Facile preparation of a CoNiS/CF electrode by SILAR for a high sensitivity non-enzymatic glucose sensor

“…Transition metal sulfides have applications in the fields of photocatalysis, 24 supercapacitors, 25 sensors 26 and solar cells 27 due to their excellent physical and chemical properties, such as redox reversibility, capacitance and conductivity. Metal sulfides like CuS, 28 CoS 29 and NiS 30 were used as nanozymes for non-enzymatic glucose sensors. Li et al prepared amorphous CoS on a reduced graphene oxide-poly(3,4-ethylenedioxythiophene) composite by electrodeposition, and the glucose sensor exhibited a linear range of 0.0002–1.38 mM, and sensitivity of 113.46 μA mM −1 cm −2 with a detection limit of 0.079 μM.…”

“… 29 Lin et al electrodeposited an α-NiS nanosphere film on ITO for glucose detection, and the sensor showed a linear range of 1–35 μM and a sensitivity of 8.4 μA μM −1 cm −2 . 30 …”